Group VII ethylene response factors forming distinct regulatory loops mediate submergence responses

Group VII ethylene response factors (ERFVIIs), whose stability is oxygen concentration-dependent, play key roles in regulating hypoxia response genes in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) during submergence. To understand the evolution of flooding tolerance in cereal crops, we evaluated whether Brachypodium distachyon ERFVII genes (BdERFVIIs) are related to submergence tolerance. We found that three BdERFVIIs, BdERF108, BdERF018, and BdERF961, form a feedback regulatory loop to mediate downstream responses. BdERF108 and BdERF018 activated the expression of BdERF961 and PHYTOGLOBIN 1 (PGB1), which promoted nitric oxide turnover and preserved ERFVII protein stability. The activation of PGB1 was subsequently counteracted by increased BdERF961 accumulation through negative feedback regulation. Interestingly, we found that OsERF67, the orthologue of BdERF961 in rice, activated PHYTOGLOBIN (OsHB2) expression and formed distinct regulatory loops during submergence. Overall, the divergent regulatory mechanisms exhibited by orthologs collectively offer perspectives for the development of submergence-tolerant crops.

Dietary patterns and diet quality among diverse older adults: the University of Alabama at Birmingham Study of Aging

OBJECTIVES

To characterize dietary patterns among a diverse sample of older adults (≥ 65 years).

DESIGN

Cross-sectional.

SETTING

Five counties in west central Alabama.

PARTICIPANTS

Community-dwelling Medicare beneficiaries (N=416; 76.8 ± 5.2 years, 56% female, 39% African American) in the University of Alabama at Birmingham (UAB) Study of Aging.

MEASUREMENTS

Dietary data collected via three, unannounced 24-hour dietary recalls was used to identify dietary patterns. Foods were aggregated into 13 groups. Finite mixture modeling (FMM) was used to classify individuals into three dietary patterns. Differences across dietary patterns for nutrient intakes, sociodemographic, and anthropometric measurements were examined using chi-square and general linear models.

RESULTS

Three dietary patterns were derived. A "more healthful" dietary pattern, with relatively higher intakes of fruit, vegetables, whole grains, eggs, nuts, legumes and dairy, was associated with lower energy density, higher quality diets as determined by healthy eating index (HEI)-2005 scores and higher intakes of fiber, folate, vitamins C and B6, calcium, iron, magnesium, and zinc. The "western-like" pattern was defined by an intake of starchy vegetables, refined grains, meats, fried poultry and fish, oils and fats and was associated with lower HEI-2005 scores. The "low produce, high sweets" pattern was characterized by high saturated fat, and low dietary fiber and vitamin C intakes. The strongest predictors of better diet quality were female gender and non-Hispanic white race.

CONCLUSION

The dietary patterns identified may provide a useful basis on which to base dietary interventions targeted at older adults. Examination of nutrient intakes regardless of the dietary pattern suggests that older adults are not meeting nutrient recommendations and should continue to be encouraged to choose high quality diets.

Dietary patterns and relationship to obesity-related health outcomes and mortality in adults 75 years of age or greater

BACKGROUND

The prevalence of obesity-related adverse health outcomes is increasing among older adults. Because it is thought that nutrition plays an important role in successful aging, there has been considerable interest in the association between dietary patterns of older adults and obesity-related health outcomes.

OBJECTIVE

This study examined the association between dietary patterns and mortality and prevalence of obesity-related health outcomes, namely cardiovascular disease (CVD), type 2 diabetes mellitus, hypertension, and metabolic syndrome (MetSyn), over a 5-year follow-up period in adults aged 75 years or greater.

DESIGN

A longitudinal observational study with cross-sectional dietary assessment.

SETTING

Rural Central Pennsylvania.

PARTICIPANTS

Community-dwelling older adults (N = 449; 76.5 years old; 57% female).

MEASUREMENTS

Multiple, unannounced, 24-hour dietary recalls were used to collect dietary intake. Cluster analysis was used to derive dietary patterns. Prevalence of CVD, diabetes mellitus, hypertension, and MetSyn was extracted from outpatient electronic medical records. Logistic regression was used to examine the associations between dietary patterns and health outcomes and mortality.

RESULTS

'Sweets and Dairy', 'Health-Conscious' and 'Western' dietary patterns were identified. Compared to the 'Health-Conscious' pattern, those in the 'Sweets and Dairy' pattern had increased odds of hypertension over the follow-up period; adjusted odds ratio (95% CI) was 2.18 (1.11-4.30). No significant associations were found for CVD, diabetes mellitus, MetSyn or mortality with dietary patterns.

CONCLUSIONS

These findings support the potential value of healthy dietary patterns in the management of hypertension in older adults. We did not observe any other strong associations between dietary patterns and health outcomes or mortality in persons ≥ 75 years of age; thus failing to support the use of overly restrictive diet prescriptions for older persons, especially where food intake may be inadequate.

Overexpression of Arabidopsis thaliana tryptophan synthase beta 1 (AtTSB1) in Arabidopsis and tomato confers tolerance to cadmium stress

Tryptophan (Trp) is an essential amino acid in humans, and in plants, it plays a major role in the regulation of plant development and defence responses. However, little is known about Trp-mediated cadmium (Cd) tolerance. Gene expression analysis showed that Arabidopsis thaliana tryptophan synthase beta 1 (AtTSB1) is up-regulated in plants treated with Cd; hence, we investigated whether this gene is involved in Cd tolerance. Exogenous application of Trp to wild-type Arabidopsis enhances Cd tolerance. Cd tolerance in the Trp-overproducing mutant trp5-1 was associated with high chlorophyll levels and low lipid peroxidation, as indicated by malondialdehyde 4-hydroxyalkenal level, whereas the wild-type developed symptoms of severe chlorosis. Moreover, the Trp-auxotroph mutant trp2-1 was sensitive to Cd. CaMV 35S promoter-driven AtTSB1 enhanced Trp accumulation and improved Cd tolerance in transgenic Arabidopsis and tomato plants without increasing the level of Cd. Moreover, reverse transcription-polymerase chain reaction confirmed that enhanced level of Trp in AtTSB1 transgenic Arabidopsis plants affected the expression of AtZIP4 and AtZIP9 metal transporters, which interfered with Cd ion trafficking, a mechanism of transcriptional regulation that does not exist in wild-type plants. Overexpression of AtTSB1 in transgenic tomato also produced higher Trp synthase-beta enzyme activity than that in wild-type plants. These results implicate that Trp could be involved in Cd defence.

Overexpression of Arabidopsis thaliana tryptophan synthase beta 1 (AtTSB1) in Arabidopsis and tomato confers tolerance to cadmium stress

Tryptophan (Trp) is an essential amino acid in humans, and in plants, it plays a major role in the regulation of plant development and defence responses. However, little is known about Trp-mediated cadmium (Cd) tolerance. Gene expression analysis showed that Arabidopsis thaliana tryptophan synthase beta 1 (AtTSB1) is up-regulated in plants treated with Cd; hence, we investigated whether this gene is involved in Cd tolerance. Exogenous application of Trp to wild-type Arabidopsis enhances Cd tolerance. Cd tolerance in the Trp-overproducing mutant trp5-1 was associated with high chlorophyll levels and low lipid peroxidation, as indicated by malondialdehyde 4-hydroxyalkenal level, whereas the wild-type developed symptoms of severe chlorosis. Moreover, the Trp-auxotroph mutant trp2-1 was sensitive to Cd. CaMV 35S promoter-driven AtTSB1 enhanced Trp accumulation and improved Cd tolerance in transgenic Arabidopsis and tomato plants without increasing the level of Cd. Moreover, reverse transcription-polymerase chain reaction confirmed that enhanced level of Trp in AtTSB1 transgenic Arabidopsis plants affected the expression of AtZIP4 and AtZIP9 metal transporters, which interfered with Cd ion trafficking, a mechanism of transcriptional regulation that does not exist in wild-type plants. Overexpression of AtTSB1 in transgenic tomato also produced higher Trp synthase-beta enzyme activity than that in wild-type plants. These results implicate that Trp could be involved in Cd defence.

Prenatal diagnosis of de novo interstitial deletion of proximal 4q by maternal serum screening for Down syndrome

Deletion of the proximal portion of chromosome 4q is apparently rare. To our knowledge, prenatal diagnosis of the interstitial deletion of 4q12-21.1 has never been reported. We present a prenatal case of 4q deletion in association with a positive Down syndrome screening test of an elevated maternal serum free beta human chorionic gonadotrophin (beta-hCG) level. The prenatal sonogram revealed intra-uterine growth retardation (IUGR) and shortening of the femur. Facial dysmorphism included micrognathia, depressed nasal bridge and low-set ears, these anomalies were evident at the postnatal examination. All of the anomalies were consistent with those described in proximal 4q deletion syndrome. Our case suggests that chromosome studies may be indicated for patients with high maternal serum free beta-hCG and IUGR in the early second trimester.